In the field of shotguns and over-and-under or coupled double-barreled shotguns, usually either single-trigger or double-trigger trigger mechanisms are used, which are mounted on a support, called the trigger guard, which can be attached to the lower part of the bascule of the gun corresponding to a suitable opening or space. The fixing into position of the trigger guard and, by means of this, of the trigger mechanism, is carried out generally, on the one hand, by the joint insertion of a tab in front of the trigger guard into a complementary seat provided in the bascule and, on the other hand, by attaching the end of the trigger guard to the bascule by means of a coupling system.
The above makes it possible to mount and to remove the trigger mechanism on the guns as a block unit.
An example of a coupling and releasing device having the above-mentioned function has become known from EP-A-277,921.
A sliding safety catch, mounted and movable in the upper part of the bascule and having its own part intended for interfering with an element of the trigger mechanism in order to inhibit the use of the latter when the gun is put on safety, is also generally coordinated with the trigger mechanism of the guns.
On the other hand, the barrels are pivoted on the bascule, rotating between a dosing position and an opening position. A top lever mounted on the bascule is provided for loading the barrels when closed and for unloading when they must be opened.
However, in the prior-art devices, the releasing of the trigger mechanism for its removal from the bascule may also be carried out not under conditions of maximum safety. In fact, such a release may also be carried out with the gun closed and when a hand of the user may interfere with the trigger, thus with the risk of involuntarily and accidentally causing the firing of a cartridge in the barrel. The same lack of safety may also be found in the attachment of the trigger mechanism to the bascule.